Cale’s manager Mike Kappus has told The Associated Press that the architect of the Tulsa Sound died Friday of a heart attack at Scripps Hospital in La Jolla, Calif.

The Oklahoma native cut a wide path through 1970s rock ‘n’ roll, influencing some of the most famous musicians at the time with songs that were laid back and mellow, yet imbued with a driving groove.

A former member of the Grand Ole Opry touring company, Cale never rose to the level of success of his admirers, but his fingerprints could be heard all over the genre in the 1970s, and his music remains influential.